Updated: Monday, September 10th, 2018 at 12:32am

Some of the medallions affixed to trees on trails throughout the Sandia Mountains. (Photos courtesy of Carl Gervais)

ALBUQUERQUE, N.M. — I’d like to imagine what happens when an impressionable hiker not well versed in the more esoteric particulars of history comes across a tree in the Sandias studded with a small metal marker that reads, Galileo’s Death Tree.

Do they fear they’ve stumbled upon an ancient site of carnage? Do they shudder at the horror of their inadvertent find? Do they worry that spirits of the damned still haunt the forest?

Do they get the heck out of there?

Surely, though, they also wonder, as do we, who affixed these mysterious medallions to these trees.

The Santa Fe Trail Tree shows a germination date of 1821, when the trade route opened. (Courtesy of Carl Gervais)

Have you seen them? By some counts, there have been as many as 88 documented medallion trees, maybe even twice as many more once, scattered along the trails throughout the Sandia Mountains like secret little jewels of history.

At present, the locations of 84 medallion trees are known.

Each medallion – an aluminum or brass or steel washer about 1½ to 2 inches in diameter – is screwed into the tree over the hole where a core sample was taken to determine the tree’s age. A historic event that corresponds with the germination date, or GD, is stamped on the medallion.

Galileo’s Death Tree, for example, lists a GD of 1642, the year Galileo died.

Most medallions commemorate far less dour moments in history.

There’s the Ben Franklin’s Kite Tree of 1752, the First UNM Classes Tree of 1892 and the First Fountain Pen Tree of 1780. There’s the First Frankfurter Tree of 1652 and the Hershey’s Chocolate Tree of 1857; George Washington’s Birth Tree of 1732 and Elizabeth I Birth Tree of 1533.

The oldest tree appears to be the Robert II Crowned King of Scotland Tree in 1371 and the youngest is the Alaska 49th State Tree of 1959.

Some of the medallions include additional information, such as the date the tree was marked or the type of tree.

Little has been written about these trees, and finding them has largely been accomplished by word of mouth or the serendipity of a summer hike.

Two are somewhere near the Chimney Canyon Trail, a steep, treacherous excursion considered one of the most dangerous hikes in the Sandias. So far, Gervais has not attempted to reach those.

He isn’t sure who is responsible for the medallions. Apparently, nobody is.

According to the Sandia Mountain Natural History Center, they are the work of an “unknown person” in the 1920s.

David Ryan, writer of the “Gentle Art of Wandering” book and website, suggests that they started as a project of the Civilian Conservation Corps, which built roads, campgrounds and picnic areas in the Sandias between 1933 and 1942.

But other medallions, such as the TWA Flight 260 Crash Site Tree of 1955, were embedded long after the CCC passed into history.

Others appear to have been replaced with newer medallions as late as 1964.